Magnetically stimulating the unaffected brain hemisphere after a stroke could encourage movement in severely disabled arms


A 30-patient study, presented at Neuroscience 2015, has found that magnetically stimulating part of the brain hemisphere unaffected by stroke can affect transient changes in patients with severely disabling post-stroke arm impairment. The study is the first to focus on the transient changes produced in stroke-affected arms by transcranial magnetic stimulation (TMS).

“Little research has looked at this severely impaired population, as a consequence, no validated treatment is available to help those with the most severe disabilities,” says Rachael Harrington a student researcher with the Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, who will present the study.

“The proof-of-principle study shows a role for control of affected arm movement in the side of the brain not affected by the stroke,” says principal investigator Michelle L. Harris-Love, member of the Center for Brain Plasticity and Repair, Georgetown University, USA and director of Mechanisms of Therapeutic Rehabilitation Laboratory, MedStar National Rehabilitation Network, USA.

Modulating function of this area using TMS altered motor function in a way that was not observed in patients with milder arm impairment. This suggests that the targeted area may have a special role in recovery for more severely impaired patients.

Follow-up studies will assess whether repeated stimulation of the unaffected side of the brain can help to “teach” it to control the impaired arm, Harrington says. “Stimulating this area repeatedly may force the brain to use this latent area.”

TMS, currently approved by the FDA only for drug-resistant depression, is being tested as a treatment for a wide variety of brain disorders.